IPhone – forwarding SMS messages to email on Iphone 4

Apple does not search for very old text messages as it makes the search much slower. There is no setting to modify the period of messages it should go through, but if you really need this then you can jailbreak and SSH into your iPhone. You can then edit the .plist file and make it search for messages that are even 2 years old.

Note: This will significantly make the searching slow.

I don't know that you'll find a free one, because it costs money to maintain a server, the server in which you need to use with some software set up to communicate with the Apple Push Notification Service ("APNS").

We use Prowl (link goes to homepage, here is an iTunes App Store Link) at work in order to send Monitoring (NAGIOS) notifications to our phones. It's a $3 app, but it's also infinitely flexible.

It gives you an e-mail address you can use to just shoot notifications too, but it also offers an API you can use to do a lot of special things with.

More details if requested after you check out Zac's site. (Zac is the developer/maintainer/operator of Prowl app and it's associated server backend.)